Drive for rolling mill

ABSTRACT

THIS INVENTION HAS TO DO WITH A ROLLING MILL CONSISTING OF THREE COOPERATING ROLLS, ONE OF WHICH IS POSITIVELY DRIVEN AND THE OTHER TWO ARE DRIVEN BY A TURBINE-LIKE MOTOR.

12, 1971 E. BRETSCHNEIDER DRIVE FOR ROLLING MILL Filed Dec. F

1 m H 8 n Ina-Mme ie/CM flfem'c/m/s/oeli m BM flTrbk/YE) 3,611,777 DRIVEFOR ROLLING MILL Erich Bretschneider, Buderich, Germany, assignor toSiemag Siegener Maschinenbau Gmb'H, Dahlbruch,

Germany Filed Dec. 5, 1969, Ser. No. 882,461 Claims priority,application Germany, Dec. 13, 1968, P 18 14 460.0 Int. Cl. B21b 35/00US. Cl. 72-249 4 Claims ABSTRACT OF THE DISCLOSURE This invention has todo with a rolling mill consisting of three cooperating rolls, one ofwhich is positively driven and the other two are driven by aturbine-like motor.

BACKGROUND OF THE INVENTION It is well known to reduce stock diameter byuse of a rolling mill of the type described in German Pat. No. 1,059,865in which three rolls are arranged around the stock path, and these rollsare displaced 120 relative to each other. However, only one roll isequipped with a drive which produces the total rolling force. The twoother rolls are connected to the drive roll by bevel gears. Because ofthe use of bevel gears, this arrangement is very expensive, and thesmallest usable roller diameter is limited to about 12 inches. Inaddition, with this arrangement, a roller adjustment is not possible.

Based on this experience, it was noted that for this type of rollingmill, one roll drive is sufficient; the two other rolls can be driven bythe driving roll causing the movement of the rolling stock. Duringentrance, the front end of the stock meets the one driven roll and thetwo non-driven rolls, and the latter have to be accelerated to theoperational speed by the rolling stock, so that considerable shockscould occur. To prevent such shocks and their effects to the rollingstock and the rolling stand, it has been suggested that the two rolls bebrought to speed by means of a small drive before the entrance of therolling stock. Such small drives mostly consist of separatelyarrangedelectric motors with gear drives permitting adjustment for the rolls.The expenditure and space requirements of such drives, however, are solarge that they have not become popular. These and other difficultiesexperienced with the prior art devices have been obviated in a novelmanner by the present invention.

It is, therefore, an outstanding object of the invention to provide arolling mill of the three roll type, wherein two of the rolls are drivenat stock rolling speed by an inexpensive drive which is simple inconstruction, yet rugged and dependable.

Another object of this invention is the provision of a rolling millusing three rolls in a 120 cluster, wherein two rolls are driven bymeans that will permit their adjustment relative to the other rollwithout difiiculty.

With these and other objects in view, as will be apparent to thoseskilled in the art, the invention resides in the combination of partsset forth in the specification and covered by the claims appendedhereto.

SUMMARY OF THE INVENTION In general, the invention lies in a rollingmill having three rolls mounted for rotation about axes lying at equalangles to each other, the rolls having grooves on their peripherieslying adjacent the path of stock movement and forming a substantiallyclosed roll pass. A high power drive is connected to one of the rolls toprovide all the power necessary to bring about stock feed anddeformation, while an auxiliary drive is connected to the other twoUnited States Patent 3,611,777 Patented Oct. 12, 1971 ice rolls, whichdrive consists of a wheel having a saw-tooth edge with a fluid streamstriking it tangentially.

BRIEF DESCRIPTION OF THE DRAWINGS The character of the invention,however, may be best understood by reference to one of its structuralforms, as illustrated by the accompanying drawings, in which:

FIG. 1 is a horizontal elevational view of a rolling mill embodying theprinciples of the present invention, and

FIG. 2 is a sectional view taken on the line IIII of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT This invention consists of arolling mill which forms a roll pass with at least three rolls whereonly one roll is equipped with a drive to supply the total rollingforces for the operation. The other rolls are equipped with an auxiliarydrive of small power output. Such a roller pass drive makes it possible,with little expenditure, to obtain a roll adjustment, takes very littlespace, and permits the use of small roll diameters. Each auxiliary driveis designed with a wheel having on its circumference impact areas towhich is applied a liquid stream. It has proven to be of advantage touse wheels which have saw-shaped teeth. It is also of advantage todirect the liquid stream through a nozzle which is arranged tangentiallyto the toothed wheel and directed against the steep flanks of the teeth.The cooling and the lubricating action of the sprayed liquid stream canbe made useful; it is also possible to arrange the wheel within ahousing which incorporates the nozzle.

Referring to FIG. 1, it can be seen that the rolling mill stand for awire rod mill train comprises three rolls 1, 2, and 3 arranged at anglesof 120. The rolls are equipped with profiles or grooves of well-knowndesign and are carried by shafts 4, 5, and 6 supported within the stand.The shaft 4 is connected to a high power driving device by a coupling(not shown), and the driving device is designed to produce the totalforce for the rolling operation.

On the shafts 5 and 6 are arranged auxiliary drive devices 7 and 8,respectively. The auxiliary drive devices 7 and 8 are called up only toperform the task of bringing the shafts 5 and 6 with the rolls 2 and 3-from the stationary condition up to the desired rate of revolution. Eachauxiliary drive device consists, as shown in FIG. 2, of a housing 9,which is mounted in the roll stand fixed relative to the supportbearings for shafts 5 and 6. The housing 9 is provided with a toothwheel 11 having sawshaped teeth on its circumference. This wheel ispositioned on an end 10 of the shaft 6. To this toothed wheel 11 isapplied a liquid stream such as Water, which originates from a nozzle12. The nozzle 12 is arranged tangentially to the wheel 11 within thehousing '9 and is connected to a conduit 13 supplying the liquid. Inthis way, the liquid stream always hits the steep-sloped flanks of theteeth and moves the wheel. This movement is transferred to the shaft 6and consequently to the roll 3. The toothed wheel may be designed with athread to tighten the rolls to the shaft and to achieve nut-and-boltaction In case use is made of the cooling or lubricating action of theliquid, the housing may be eliminated completely, or can 3 It is obviousthat minor changes may be made in the form and construction of theinvention without departing from the material spirit thereof. It is not,however, desired to confine the invention to the exact form herein shownand described, but it is desired to include all such as properly comewithin the scope claimed.

The invention having been thus described, what is claimed as new anddesired to secure by Letters Patent is:

1. A rolling mill for attenuating elongated stock, comprising (a) threerolls mounted for rotation about axes lying at equal angles to eachother, the rolls having grooves on their peripheries lying adjacent thepath of the stock and forming a substantially closed roll pass, (b) ahigh power drive connected to one of the rolls only to provide theentire power necessary to bring about movement of the stock through theroll pass and its deformation, and (c) an auxiliary drive for the othertwo rolls consisting 4- of a wheel formed with impact areas around itscircumference and a fluid stream impinging on the impact areas to rotatethe wheel.

2. A rolling mill as recited in claim 1, wherein the wheel is formedwith a saw-tooth circumferential formation.

3. A rolling mill as recited in claim 2, wherein the fluid streamconsists of a jet extending tangentially to the wheel against steepslopes of the teeth.

4. A rolling mill as recited in claim 1, wherein the wheel rotates in ahousing and the fluid stream originates in a nozzle mounted on thehousing.

References Cited UNITED STATES PATENTS MILTON S. MIEHR, Primary Examiner

